Equal movement system



Jlne 1945. J. P. PHILLIPS 2,373,497

EQUAL HOVEMENT SYSTEM Filed Dec. 10. 1942 /27 /29 1 k ,L -/32 WKWQJO 1[34V r136 .L 125 A4? l 0 I20 /2/ JI- :4

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JOHN P. PHILLIPS ATTDR E) Patented-lune 19, 1945 2,378,497 EQUALMOVEMENT SYSTEM John P. Phillips, North Hollywood, Calif., asslgnor,

by mesne asslgmnents, to Bendix Aviation Corporation, South Bend,11111., a corporation of Delaware Application December 10, 1942, SerialNo. 468,505

3 Claims.

This invention relates to means for equalizing movement oi two motors,and more particularly to an electrically controlled equalizer valve forfluid pressure power systems.

There are many applications where it is desirable to move two or moremotors at substantially the same speed when a mechanical interlock isnot practicable. For example, on airplanes, both flaps must be loweredand raised at the same rate to maintain the aerodynamic balance of anairplane. The present invention may therefore be used an airplane flaps.replacing the complicated cable interlock now used when separate fluidor electrical motors are used.

It is an object of the invention to provide means to equalize movementbetween two or more motors. Q

It is another object to provide an exact equalizer valve for fluid powersystems.

It is another object to provide an equalizer for fluid power systemswhich operates effec- 1t iively on bothpressure flow and upon exhaustStill another object of the invention is to provide an electricallycontrolled equalizer valve for fluid power systems.

In the drawing forming a part of this specification: I

Figure 1 is a schematic view of a fluid power system for operating theflaps of an airplane, which system incorporates the invention; and

Figure 2 is a schematic view of an electric power system for operatingthe flaps of an air plane, which system incorporates the invention.

Referring to Figure 1, a reservoir It! holds hydraulic or gaseous fluidunder atmospheric pressure, which fluid passes through a conduit II to apower driven pump it which delivers its output to a tube I6 leading to afour-way valve 2|! manually operated by a handle 2|. In the position ofvalve 20 as shown, fluid under pressure is delivered into a conduit 22leading to an equalizer valve 24 having a metering piston 26 slideabletherein. Equalizer valve 2| has two outlets. one connected to a righthand conduit 28 leading to one end of a double act ng power cylinder 30having a piston and rod 32 connected to an airplane flap 3 pivoted at36. A left hand outlet of equalizer valve 24 i connected to a conduit 38leading to one end of a double acting power cylinder having a piston androd I! connected to a second airpane flap H pivoted at 45. The oppositeends of cylinders 30 and Ill lead into a conduit 48 connected by tube 50to connected to wire E5.

the four-way valve 20, and in the position shown conduits 4B and 50deliver an exhaust fluid through four-way valve 20 and a conduit 52 toreservoir ill.

The electric circuit of Figure 1 includes a battery 54 supplying currentthrough a wire 58 to two switches 58 and Boat the four-way valve 20.These switches are normally open, but when the four-way valve 20 isoperated from a neutral position to one of the two operating positions,one or the other of these switches is closed. Switch Gil passes currentfrom wire 56 to a wire 52 connected to a wire 65. Switch 58 passescurrent from wire 56 to a wire 63 connected to a wire 64 also nearbattery 5!. Adjacent to flap N is an arcuate resistance 66, the innerend of which is connected to one end of wire Bl. The other end of wire64 is connected to the inner end of an arcuate resistance Gil adjacentto flap 3!. The outer ends of resistances E6 and 68 are A movablecontact III is connected to flap 44 and driven thereby and has electricconnection through a wire 12 and a solenoid ll back to the negative sideof battery 5|. Flap 3 drives a similar movable contact l8 electricallyconnected by a wire 18 and solenoid III to the negative side of battery54 also. A magnetically attracted rod 82 is placed in sole noids ll andI0 and has pivoted thereto a rocker arm 84 pivoted at 86 and held in aneutral position by centering springs 88. Rocker arm N moves meteringpiston 26 one way or the other, depending upon the relative strength ofsolenoids .14 and all.

In' operation, if the pilot desires to raise his flaps he operatesmanual valve 20 to the position shown, causing fluid under pressure toflow through equalizer valve 2| and into the inner ends of actuatingcylinders 30 and In. This movement also closes switch 60, passingcurrent to wire 62 and thence to wire 65. The fluid forces piston rods32 and 42 respectively outwardly, causing the flaps 34 and H to rotateabout their respective pivots. If due to mechanical friction oraerodynamic diiierences in loading. one flap advances faster than theother, the resistance will be increased in the effective circuit of thesolenoid H or of the faster flap. causing a greater current-in theslower flap circuit. This will draw rod 82 towards that solenoid,shifting metering piston 26 in a direction to limit fluid flow to thefaster actuating cylinder. The faster actuating cylinder is thus stoppedor slowed in its movements until the other actuating cylinder reachesthe same relative position, at which time the electric forces onarmature 82 are equalized and centering springs 88 return rocker arm 04to its neutral position.

It will be noted that the electric control of metering piston 20operates eifectively on exhaust flow also. The flow is reversed byrotating manual handle 2| ninety degrees in a clockwise movement,opening switch but closing switch 50 so that the current is passed towire 04. Here again the fasterflap will have the greater resistance inits circuit, operating the valve. When the flaps are not being operated,the valve 20 is in a neutral position, at which point neither switch 00nor 50 is closed and no current is wasted in the equalizing system.

The system of Figure 2 is similar to that of Figure 1 except thatelectric motors are used instead of hydraulic motors as the powersource. A battery I00 has both terminals connected to a two-way switch i02 which may alternatively connect a wire I04 leading to electric motorsI06 and I00 to either the positive or negative side. threaded shaft IIOon which a is moved, which dr ves flap Electric motor I00 has a similarthreaded shaft IIG with a threaded rider IIO driving a flap I20 pivotedat I2I. The elec tric circuit to motors I00 and I00 is completed by awire I22 having an arcuate resistance I24 placed therein.

The control circuit includes a battery I20 having one terminal connectedto a switch I2 I which connects the battery to either a wire I28 or awire I20 having circular resistances I20 and I32 connected at eitherend. Flap I20 has a takeofl I04 connected thereto and electricallyconnected by'a wire I30 and solenoid I30 to the negative side'ofbatteryI20. Flap II4 has a pointer I40 connected by a wire I42 and solenoid I44to the negative end also of battery I26. A floating armature I46 isplaced in solenoids I30 and I44 and is pivoted to a pointer arm I40pivoted at I50 and held in a neutral position by centering springs I42.The other end of switch I02 is connected to pointer I40 and the pointerin turn contacts semi-circular resistance I24. It will be noted thatswitches I02 and I2! are mechanically interconnected to act together.

To operate the flaps of Figure 2, the pilot moves switch I02 (andlikewise switch I21) to one position or the other, causing the motors torotate and the flaps I20 and H4 to move. If one flap gets ahead of theother it will draw alarger (or smaller) current than the other, which isreflected in solenoids I00 and I44. Whenthe solenoids are unbalancedthey cause armature I00 to move, moving pointer Ill and increasing theamount of resistance in the circuit of the faster motor, slowin thatmotor until the other motor assumes a similar relative position. Thus,th circuit described can be used to control an electric source as wellas a hydraulic or pneumatic source of power.

Although this invention has been described with reference to flaps on anairplane it is not limited to such a narrow application, since this II4pivotedat H5.

was done for purposes of illustration only, nor is the applicationlimited in any other way except by the terms of the following claims:

I claim:

1. A power system comprising: a pair of reversible motors, Velectrically operated equalizer means to equalize the speeds of themotors, variable resistor means operated in accordance positions of saidmotors to control the equalizer means, each variable resistor meanscomprising a pair of end terminals and a tap terminal, and meansoperated by movement of the associated motor to inversely vary theresistances between the tap terminal and the respective end terminals,said tap terminals being connected to said equalizer means, means todeliver electric current to either end terminal of each variableresistance means and through the tap terminals to said equalizer means,and switch means dependent upon the direction of operation of saidmotors for supplying current to one or the other of the end terminals ofsaid resistance means.

2, A power system comprising: a pair of reversible motors, equalizermeans to equalize the speeds of the motors, variable resistor meansoperated by the operative positions of said motors to control saidequalizer means, each variable spective end terminals, means to deliverelectric current to either end of said resistor means and through thetap terminals of said resistor means to said equalizer means, switchmeans dependent upon the direction of operation of said motor forsupplying current to one or the other end terminals of said resistormeans, and means to cut oil all current to said resistor means when saidmotors are not being operated.

3. In a power system having a pair of motor devices to be operated inunison, electrically operextent corresponding to the extent of movementof the motor device, means for supplying current to one of said windings

